Sheet glass drawing machine



J. H. REDSHAW SHEET GLASS DRAWING MACHINE Filed Jan. 16, 1940 Nov. 3, 1942.

5 Sheets-Sheet 1 INVENTQR.

JOSEPH H. REDSHAW.

A TTORNEY Nov. 3, 1942. J. H. REDSHAW SHEET GLASS DRAWING MACHINE Filed Jan. 16, 1940 H D 70fill 60 5 Sheets-Sheg 2 INVENTOR JOSEPH H. REDSHAW aws 4;.

' ATI'OR EY.

NOV. 3, 194.2. J REDSHAW 2,300,522

SHEET GLASS DRAWING MACHINE Filed Jan. 16, 1940 5 Sheets-Sheet 3 L 22 IN VEN TOR.

JOSEPH H. REDSHAW Nov. 3, 1942.

J. H. REDSHAW 2,300,522

SHEET GLASS DRAWING MACHINE Filed Jan. 16, 1945 5 Sheets-Sheet 5 INVENTOR. JOSEPH H. REDSHAW Patented Nov. 3, 1942 2,300,522 SHEET GLASS DRAWING MACHINE Joseph H. Redshaw,

County, Pa., a corporation of Pennsylvania.

Homestead, Pa., assignor to Pittsburgh Plate G lass Company, Allegheny Application January 16, 1940, Serial No. 314,061

2 Claims.

This invention relates to glass drawing apparatus and it has particular relation to an improved assembly of elements designed to insure uniformity of drawing roll operation, compensation for tendency of heating 'in bearings, adjustability of rolls, together with improved operation of their driving and associated elements.

One object of the invention is to provide an improved glass drawing apparatus having bearings cooled and oiled by circulating systems to provide for the use of precision bearings in supporting drawing rolls and other elements.

Another object of the invention is to provide an improved non-play worm gearing transmission from a source of power to driven drawing rolls of the apparatus.

Another object of the invention is to provide an improved chain transmission from the directly driven drawing rolls to companion swinging or front rolls.

Another object of the invention is to provide an improved coupling structure especially adapted to conditions imposed upon the transmission shafts of glass "drawing apparatus.

Another object of the invention is to provide an improved structure for swinging and aligning drawing rolls.

Heretofore, there have been proposals for gear driven rolls in glass drawing apparatus, but on account of unfavorable conditions of heat and need for precision in operation, great difficulty has been experienced in providing a type 'of gear which responds without unsatisfactory play and other adverse results as to roll action, such as formation of so-called roll marks, which are often Visible on the surface of drawn glass. By employing precision bearings which are protected by an improved arrangement of fluid circulating and lubricating systems, as described here n, the

roll marks canbe obviated.

In one arrangement, according to the improved invention, lower rolls of the apparatus are swingable on bell cranks, including the lower rear rolls which are ordinarily in a stationary position during the operation of the apparatus. These lower rear rolls are adjustable with precision in aligning them with the proper plane of drawing, although they can be released and separated from companion front rolls with which they are arranged in horizontal pairs. After adjustment or swinging, they can be fastened without disturbing their precision alignment. The front rolls are all mounted upon weighted bell cranks by which proper pressure can be exerted upon sheet glass between pairs of rolls for drawing the glass. The front and rear drawing rolls areso mounted in their bearings that one or more of them can be released and removed without affecting the continuous operation of the apparatus. r

In the drawings:

Fig. 1 is a fragmentary side elevation of a glass drawing apparatus; Fig. 2 is a fragmentary view partially in front elevation and partially in vertical section taken substantially along the line 11-11 of Fig. 1. Fig. 3 is a view partially in side elevation and partially in vertical section of the side of the glass drawing apparatus opposite that shown in Fig. 1; Fig. 4is a fragmentary horizontal section taken substantially along the line IV-IV of Fig. 2 and including illustration of both front and rear rolls; Fig. 5 is a fragmentary diagrammatic illustration of bearing supports and. fluid circulation system for operating parts of the apparatus; Figs. 6 and 'Z are similarfragmentary diagrammatic side elevations illustrating the application of fluid circulation systems; Fig. 8 is 'a fragmentary elevation of adjusting and controlling elements for the apparatus; Figs. 9 and 10 are longitudinal fragmentary sections on a larger scale of shaft and bearing construction employed in the apparatus; Fig. 11 is a cross section'on a larger scale of a coupling for a transmission shaft; and Fig. 12 is, a plan of a key employed in the coupling.

'In practicing the invention, a glass drawing apparatus or leer structure in which sheet glass 22 is adapted to be drawn upwardly from a molten bath is provided rigidlv thereon with a support 23 on which a motor 25 is anchored.

The motor operates a vertical sectional shaft 26 by means of spiral or worm gears 21 and 28 connected rigidly to the drive shaft 29 of the motor and to the vertical shaft 26. respectively. The sectional shaft 26 is connected among its sections by means of spaced couplings 35, each of which is aligned with adjacent shaft sections,

,by means of split keys having oppositely extending split portions 31 formed longitudinally therein and fitting inkeyways 38 formed in the coupling and shaft. Suitable screws 39 threaded through the body of each coupling engage in conical recesses 48 formed in the keys along the split portions thereof for sp eadin the latter and tightening, the couplings on the shaft sections to take up any play hat mi ht ex st after they have been assem led and after the apparatus has been heated preparatory to the beginning of the drawing operations.

.Suitable bearings 50 of precision type carried v able bar 91 taining one in a series of spaced bearing jackets 52 that are rigid with the leer structure support the shaft in its vertical position. Each bearing Jacket 52 cooperates with an oppositely disposed bearing jacket 53 (Fig. 4) rigidly carried on the opposite sides of the leer for the purpose of rotatably supporting one roll 54 of a pair of drawing rolls 54 and.55. The other roll 55 of this pair is provided with oppositelydisposed bearing jackets 60 in which it is rotatably mounted in its bearings 52.

A number of pairs of these rolls are spaced vertically in the leer and each roll 54 is driven from the vertical shaft 26 by'means of intermeshing spiral or worm gears 56 and 51 connected rigidly to the shaft and roll, respectively. One end of each roll 54 and 55 is provided with a separable section 03 slidable, aind'non-rotatably carried coaxially, with respect to its roll, but rotatable with such roll, and from which the latter can be disconnected and removed through an opening 54 formed in the wall of theleer. Plates 65 normally bolted, as indicated at 66, to the leer serve as shields for the bearing jackets 53'and 62 to protect them from inside heat of the leer. Openings '6! in the plateare of such size as to permit proper play or, adjustability of the rolls whilethey are being aligned and during the operation of the apparatus.

Each jacket 60 is suspended rigidly upon an upright swinging arm 68 of a bell crank I that is rotatably mounted on a stud shaft I2 carried rigidly upon the leer and that also has 'a substantially horizontal arm 13 upon which an'adjustable weight 'I4isslidable. 1

Each of the two lower rolls "is also carried by a bell crank I6, which has an upright arm 11 in which the roll 15 is suspended in a bearing jacket 18. A substantially horizontal arm I9 of the bell crank is provided with an adjustable slidable weight 80 thereon. Each roll 15 is thus swingable although normally aligned vertically with the rolls 54. These bell cranks are mounted upon stud shafts 8| carried rigidly in the leer structure and the position of each of the two lower rolls I5 can be established withprecision by means of a stop bolt 82 adjustably threaded through a bracket 83 that is rigid on the leer. The lower side-of the arm I9 rests upon'the end of the bolt. 82 and a clamping cam lever 84 (Figs. 1 and 8) having a cam face 86 is rotatably mounted, as indicated at 85, on a bearing bracket 81 that is carried on the leer above each arm I9. This lever cooperates with the bolt 82 to lock the arm in a predetermined position by wedging the cam face against the upper portion of the arm. A, weighted lever arm 88 extends laterally from the lever'84 and constantly exerts force pressing, or tending to press, the cam face into locking relation with the arm 13.

Cables." and ill are connected at their inner ends to arms 92 of the cam levers and to arms I0, respectively, from which they are trained over pulleys 95 rotatably carried, as indicated at 96, upon the motor support 23 and the outer ends of these cables are connected to a manually operhaving a pivotal connection 98 with the leer. One cable 9| is substantially longer than the other cable'30 for the purpose of mainof them taut and the other slack, as shown in Fig. 1, and thus, the cables are operable by the bar 31 for first lifting the outer ends of the lever arms 92 and then lifting the outer ends of the arms I3 in effecting the adjustment of the two lower rolls I5.

' bly carried upon a as the bell cranks sprocket chain I42 A plurality of lower rolls I00 corresponding to the rolls 55 and in substantially vertical alignment therewith are also movable by means of cables I02 having their inner ends connected to the outer ends of the lever arms I3- and outer cable ends are connected'to manually operable bars I03 pivoted, as indicated at I04, upon the leer. Intermediate portions of cables I 02 are trained over pulleys I05 carried rotatably, as indicated at I06, upon an upper frame member I0! 01' the leer structure. Suitable latches IIO pivoted upon a rod II2 that is mounted upon the leer frame are engageable with the bars I03 to hold them in lowered position after they have been operated to pivot the roll suspending lever arms 60 in such manner as to move the lower rolls outwardly. Since the mountings of the lower rolls I00 are substantially the same as those for the upper rolls 55, the same reference characters are employed for the parts associated therewith, such I0 and bearing jackets 60. It should be noted thateach of the rolls has its opposite ends outside the leer casing wall in order that the supporting bearings may be as far tical transmission shaft and for the various rolls communicates with flexible inlet conduits I20 through which cooling fluid, such as water, can be circulated and then exhausted through flexible fluid conveying outlet conduits I22. Likewise each bearing enclosed in fluid tight relation in the Jacket communicates with flexible oil conveying inlet conduits I30 through which oil is circulated through ducts I32 to the bearings and then exhausted therefrom through oil conveying outlet conduits I33.

In transmitting power from the vertical shaft 26 both the stationary and swinging rolls are provided with sprockets, one of which designated I40 is rigidly carried by each roll 54 and engages a that has one of its reaches trained thereover.

v stud shaft I45 rigid in the leer receives the chain at one extremity of its path and a'double sprocket I46 receives the chain at the other extremity of the path. The double sprocket is rotatable upon the stud shaft 12 coaxially with respect to the axis of swinging of the bell crank I0. Another chain I50 is trained over the'double sprocket I46 adjacent the chain I42 and also over a sprocket I52 carried rigidly upon an end portion of each swinging roll 55. In this arrangement the swinging rolls 55 can be rotated at-a constant speed corresponding to the speed of the rolls 54, while at the same time permitting the swinging thereof.

As shown in Fig. 9, each stud shaft I2 has an eccentric section I55 upon which the double sprocket I46 is rotatably mounted and the shaft can be rotatably adjusted in its supporting socket An idler sprocket I43 rotataon the leer by means of a suitable set screw or bolt I63 screw threaded through the wall of the socket. Thus the chain I42 can be tightened without changing the relative positions of the upon spaced eccentric stud shafts I16 also receive the chain I which is likewise trained about the double sprockets I46 of the three lower bell crank supports 12.

In this portion of the apparatus, a sprocket chain I11 is trained about the double sprocket I12 and about a roll driving sprocket I18 rigidly carried upon the end of each lower roll 15 in the same manner as the chain ISO is associated with each roll 55.

Each stud shaft 8I has an eccentric section I80 upon which the double sprocket I12 is mounted and the shaft can be rotatably adjust-ed in its supporting socket I82 on the leer by means of a conventional set screw or bolt I83 screw threaded through the wall of the socket. The chain I19 can be tightened without changing the relative position of each roll 15 and its supporting stud shaft 8I because the bell crank 16 is mounted upon a non-eccentric section I85 of the stud shaft. Each stud shaft I16 (Fig. 5) has an eccentric section I98 upon which the sprocket I15 is mounted and the shaft can be rotatably adjusted in its socket I92 on the leer by means of a suitable set screw or bolt I93 screw threaded through the wall of the socket. Thus the chain I10 can be tightened without changing the relative positions of the sprockets I12, I18 or I46, I52 independently of the adjustment effected by means of the From the foregoing description, it will be apparent that the various features described cooperate to produce an extremely smoothly running glass drawing apparatus, in which the vertical shaft 26 has direct driving contact with the several stationary rolls in such manner that there can be no appreciable play during the operation. There can, therefore, be no trembling or vibration of the drawing rolls. Such play is obviated by the use of worm gears, as described. Likewise, each of the upper pair of rolls has a chain drive from each stationary roll to its companion swinging roll 55, and the latter roll of each pair can be maintained in its proper driving relation and without danger of play occurring by manipulating the eccentric shafts 12 and I45 to insure constant tautness in the chain drive.

In order to facilitate the precision alignment of the lower rolls which first receive the glass sheet from the molten bath, these lower rolls of each pair are mounted upon bell cranks on opposite sides of the plane of drawing and a common sprocket chain provides for maintaining the operation of these lower rolls in proper relation to eccentric sections I80, I55 of the stud shafts 8|,

the operation of the upper rolls. Likewise, by including the continuous flow of lubricating fluid to the end bearing of the rolls and, at the same time,

providing for continuous flow of cooling fluid, such as water, to the jackets surrounding the bearings, an extremely accurate and uniformly operating glass drawing unit is insured.

Although considerable variation in structure of the several parts of the invention has been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited, but that various changes can be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. In an apparatus for drawing sheet glass from a molten bath substantially along a predetermined vertical plane and including an upright supporting leer casing, a series of pairs of drawing rolls normally arranged successively in substantial alinement in the leer casing, at least one pair of the rolls including a normally stationary roll and a movable roll, a bell crank having an upright arm supporting each end of double sprocket, an additional sprocket connecting said second chain in driving relation to said movable roll to swing with said upright arm, and a vertical driven shaft rotatably mounted upon the leer casing, said stationary roll and driven shaft having meshing worm gears thereon for driving the stationary roll.

2. In an apparatus for drawing sheet glass from a molten bath substantially along a predetermined vertical plane and including an upright supporting leer casing, a series of pairs of drawing rolls normally arranged successively in substantial alinement in the leer casing, at least one pair of the rolls including a normally stationary roll and a movable roll, a bell crank having an upright arm supporting each end of said movable roll for lateral movement thereof, each bell crank having a lateral arm, a supporting bearing shaft carrying each bell crank on the casing at the junction of the arms, said bearing shaft having an eccentric portion and being rotatably adjustable in said casing, a double sprocket rotatable on the eccentric portion of said bearing shaft, an idler sprocket eccentrically adjustable on said casing and having a chain trained therefrom to the double sprocket, said stationary roll having a sprocket engaging said chain between the double sprocket and the idler sprocket, a second chain trained about said double sprocket, an additional sprocket connecting said second chain in driving relation to said movable roll to swing with said upright arm, and a vertical driven shaft rotatably mounted upon the leer casing, said stationary roll and driven shaft having intermeshing worm gears 

